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influence of Luther

...bread and wine, however, do not change their substance, and, for Luther, there was no miracle of the mass in which the priest was thought to alter the substance of the sacrifice. This view undercut
sacerdotalism, which emphasized the intermediary role of the priest between God and humankind, since the words of the priest did not bring the body of Christ to the altar. The undercutting of...

relation to monastic status

In addition to organizational and institutional forms, a typology is needed to classify monastic status and hierarchy. The first and most important such division is between sacerdotal and nonsacerdotal full-time supererogatory specialists. Most of the canon-based, or scriptural, religions of the world distinguish between priests and nonpriestly practitioners. In the case of Eastern Orthodox and...

ruling classes of Christendom

...of the universities, the threefold structure of the ruling classes of Christendom was established:
imperium (political authority),
sacerdotium (ecclesiastical authority), and
studium (intellectual authority). The principle that each of these classes was independent of the other...